Does anyone elses' grand marquis make a hissing noise from the dash like by the gear box thing?? It sounds like a leaking tire, but its coming from the gear box. Can anyone help??

wow...i didnt have that problem with mine...sorry.

Well, I don't know, but it goes away the faster I go. It's really loud when I'm idling. I really don't get it. I had an '85 and it did the same thing. But you say yours doesn't do it. Sooo, now I don't know.. do you think maybe it could exhaust leak???

Does your car have vacuum operated heater controls?

I beat its a vac leak either the a/c control or brake booster. Try disconnecting each one at a time and pluging them, then check for the noise. good luck

Hmmm...thanx I will try that.

The vac to the a/c is color coded the black is the feed. You can find on the outside pass. side in engine compart. there is 2 hose to in/out of firewall. One goes to the heater hose valve. the other to a vac dist. on firewall or intake manifold. The later one is the one you want to remove and plug.

You know that would make some sense because there is a water leak somewhere by the heater core, but Im not to sure where. But it only leaks when I have been driving it for a while. So I don't know, I will get to the bottom of it eventually.

Amanda,
The water leak sounds like you have a clugged a/c condensation drain. Let me guess it also only leak if a/c is on and if you drive for a while. If this is so, it is a very easy fix. Find the drain hose under vehicle on pass. side, and use a small pick to remove any abstrusion. Then use air hose to blown clean, see if this helps. [img]smileys/smiley2.gif[/img]

Hmm....but I don't use my a/c. I live in Indiana, you don't need a/c. I dunno, it doesn't do it all the time. I will firgure it out one day I guess. I don't have a garage to actually work on my car so...I cant really do much to it.f